(1) Field of the Invention
The present invention relates to a method and apparatus for treating seeds, thereby reproducibly enhancing rate and uniformity of seed germination, early growth, root growth, maturity, and yield in food crops and other plants. These results are achieved by exposing seeds or growing plants to uniform, spontaneously-organized pulses of ion-electron avalanches. One important aspect is allowing a period of several weeks storage before planting thereby allowing internal, biochemical changes to take place at the cellular level within the seed. The present invention also relates to a quality-control method and apparatus for selecting optimal treatment parameters with the avalanches of ions and electrons for each variety of seed.
(2) Description of Related Art
Almost since the discovery of the commercial use of electricity, experimenters have tried to electrically influence plant growth. Various prior art experimenters have claimed positive results from exposing growing plants to electrical stimulation in situ. A wiring network over a field of growing crops is not cost-effective or practical on a commercial scale, and such techniques have not been adopted by farmers.
Some prior art experimenters have attempted to avoid the prohibitive cost of wiring a field by applying electromagnetic treatments to seeds before planting. Despite reports of increased growth and, in some cases, increased yield, these results have proven difficult to repeat and have not achieved commercial use. Parry (U.S. Pat. No. 2,308,204 (1943)) describes the use of an oscillating DC voltage to treat seeds to increase germination of the seeds. There is no indication of improved plants. Jonas (U.S. Pat. No. 2,712,713 (1955)) and others exposed seeds to high frequency oscillating fields between 30 MHz and microwave range, claiming faster and more uniform germination. Jonas stated that the work of others along similar lines have been impossible to repeat and confirm. The patent describes only increased germination of the seeds. Amburn (U.S. Pat. Nos. 3,675,367 (1972) and 3,765,125 (1975)) exposed seeds to magnetic fields, claiming increased germination rate as an effect. Because of unreliability and non-reproducibility, none of these methods have achieved widespread commercial acceptance.
Levengood (U.S. Pat. No. 3,822,505 (1974)) describes an apparatus for genetically altering plant cells using combined electrical and magnetic fields. The electrical field is static. There was alteration in the growth of seeds, but the method was not repetitively effective from batch to batch of seeds. Another patent to Levengood (U.S. Pat. No. 3,852,914 (1974)) describes a method for testing seeds for viability, by measuring pregermination tissue conductivity.
Schiller et al (U.S. Pat. No. 4,633,611 (1987)) describe treating seeds to disinfect them with low energy electrons using an electron gun. The radiation dosages are quite high and the acceleration voltages are between 25 and 75 kV. The use of high energy ionizing radiation can cause damage to chromosomes and resultant genetic change which poses complications for use in open fields. There is no indication that the growth of the plant is enhanced on a reproducible basis. Yoshida (U.S. Pat. No. 4,758,318 (1988)) describes using a pulsating direct current to prevent mold. The voltages were 300 to 20,000 V DC which were pulsed. This method is not practical on a large scale and the results were variable. Liboff et al (U.S. Pat. No. 5,077,934 (1992)) describe the use of magnetic fields with plants in the soil. This method is not practical.
Levengood (U.S. Pat. No. 5,288,626 (1994)) describes genetically transferring DNA between plants using a constant DC voltage. This is also described in Bioelectrochemistry and Bioenergetics (1991). These are techniques for producing genetically altered plants.
Other patents of general interest are Saruwatari (U.S. Pat. No. 4,188,751 (1980)) relating to magnetic treatment; Weinberqer (U.S. Pat. No. 3,703,051 (1972)) relating to ultrasound; U.S. Pat. No. 3,940,885 (1976) relating to microwaves.
One system which used an A.C. ripple in a D.C. current to produce pulses is Tellefson (U.S. Pat. No. 5,117,579 (1992)). Pulses of ions were produced from wire brush emitters to flood growing plants in a field. The method is not used with seeds.
There is clearly a need for a reproducible and reliable method for treating seeds to enhance their growth characteristics. The prior art methods have not met this need since no such method is used commercially.